![Sasha Levin](/assets/img/avatar_default.png)
I'm not sure why, but the hlist for each entry iterators were conceived list_for_each_entry(pos, head, member) The hlist ones were greedy and wanted an extra parameter: hlist_for_each_entry(tpos, pos, head, member) Why did they need an extra pos parameter? I'm not quite sure. Not only they don't really need it, it also prevents the iterator from looking exactly like the list iterator, which is unfortunate. Besides the semantic patch, there was some manual work required: - Fix up the actual hlist iterators in linux/list.h - Fix up the declaration of other iterators based on the hlist ones. - A very small amount of places were using the 'node' parameter, this was modified to use 'obj->member' instead. - Coccinelle didn't handle the hlist_for_each_entry_safe iterator properly, so those had to be fixed up manually. The semantic patch which is mostly the work of Peter Senna Tschudin is here: @@ iterator name hlist_for_each_entry, hlist_for_each_entry_continue, hlist_for_each_entry_from, hlist_for_each_entry_rcu, hlist_for_each_entry_rcu_bh, hlist_for_each_entry_continue_rcu_bh, for_each_busy_worker, ax25_uid_for_each, ax25_for_each, inet_bind_bucket_for_each, sctp_for_each_hentry, sk_for_each, sk_for_each_rcu, sk_for_each_from, sk_for_each_safe, sk_for_each_bound, hlist_for_each_entry_safe, hlist_for_each_entry_continue_rcu, nr_neigh_for_each, nr_neigh_for_each_safe, nr_node_for_each, nr_node_for_each_safe, for_each_gfn_indirect_valid_sp, for_each_gfn_sp, for_each_host; type T; expression a,c,d,e; identifier b; statement S; @@ -T b; <+... when != b ( hlist_for_each_entry(a, - b, c, d) S | hlist_for_each_entry_continue(a, - b, c) S | hlist_for_each_entry_from(a, - b, c) S | hlist_for_each_entry_rcu(a, - b, c, d) S | hlist_for_each_entry_rcu_bh(a, - b, c, d) S | hlist_for_each_entry_continue_rcu_bh(a, - b, c) S | for_each_busy_worker(a, c, - b, d) S | ax25_uid_for_each(a, - b, c) S | ax25_for_each(a, - b, c) S | inet_bind_bucket_for_each(a, - b, c) S | sctp_for_each_hentry(a, - b, c) S | sk_for_each(a, - b, c) S | sk_for_each_rcu(a, - b, c) S | sk_for_each_from -(a, b) +(a) S + sk_for_each_from(a) S | sk_for_each_safe(a, - b, c, d) S | sk_for_each_bound(a, - b, c) S | hlist_for_each_entry_safe(a, - b, c, d, e) S | hlist_for_each_entry_continue_rcu(a, - b, c) S | nr_neigh_for_each(a, - b, c) S | nr_neigh_for_each_safe(a, - b, c, d) S | nr_node_for_each(a, - b, c) S | nr_node_for_each_safe(a, - b, c, d) S | - for_each_gfn_sp(a, c, d, b) S + for_each_gfn_sp(a, c, d) S | - for_each_gfn_indirect_valid_sp(a, c, d, b) S + for_each_gfn_indirect_valid_sp(a, c, d) S | for_each_host(a, - b, c) S | for_each_host_safe(a, - b, c, d) S | for_each_mesh_entry(a, - b, c, d) S ) ...+> [akpm@linux-foundation.org: drop bogus change from net/ipv4/raw.c] [akpm@linux-foundation.org: drop bogus hunk from net/ipv6/raw.c] [akpm@linux-foundation.org: checkpatch fixes] [akpm@linux-foundation.org: fix warnings] [akpm@linux-foudnation.org: redo intrusive kvm changes] Tested-by: Peter Senna Tschudin <peter.senna@gmail.com> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Sasha Levin <sasha.levin@oracle.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Gleb Natapov <gleb@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
673 lines
16 KiB
C
673 lines
16 KiB
C
/*
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* (C) 2012 Pablo Neira Ayuso <pablo@netfilter.org>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation (or any later at your option).
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*
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* This software has been sponsored by Vyatta Inc. <http://www.vyatta.com>
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*/
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#include <linux/init.h>
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#include <linux/module.h>
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#include <linux/kernel.h>
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#include <linux/skbuff.h>
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#include <linux/netlink.h>
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#include <linux/rculist.h>
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#include <linux/slab.h>
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#include <linux/types.h>
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#include <linux/list.h>
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#include <linux/errno.h>
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#include <net/netlink.h>
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#include <net/sock.h>
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#include <net/netfilter/nf_conntrack_helper.h>
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#include <net/netfilter/nf_conntrack_expect.h>
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#include <net/netfilter/nf_conntrack_ecache.h>
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#include <linux/netfilter/nfnetlink.h>
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#include <linux/netfilter/nfnetlink_conntrack.h>
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#include <linux/netfilter/nfnetlink_cthelper.h>
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MODULE_LICENSE("GPL");
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MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
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MODULE_DESCRIPTION("nfnl_cthelper: User-space connection tracking helpers");
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static int
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nfnl_userspace_cthelper(struct sk_buff *skb, unsigned int protoff,
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struct nf_conn *ct, enum ip_conntrack_info ctinfo)
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{
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const struct nf_conn_help *help;
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struct nf_conntrack_helper *helper;
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help = nfct_help(ct);
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if (help == NULL)
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return NF_DROP;
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/* rcu_read_lock()ed by nf_hook_slow */
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helper = rcu_dereference(help->helper);
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if (helper == NULL)
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return NF_DROP;
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/* This is an user-space helper not yet configured, skip. */
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if ((helper->flags &
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(NF_CT_HELPER_F_USERSPACE | NF_CT_HELPER_F_CONFIGURED)) ==
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NF_CT_HELPER_F_USERSPACE)
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return NF_ACCEPT;
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/* If the user-space helper is not available, don't block traffic. */
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return NF_QUEUE_NR(helper->queue_num) | NF_VERDICT_FLAG_QUEUE_BYPASS;
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}
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static const struct nla_policy nfnl_cthelper_tuple_pol[NFCTH_TUPLE_MAX+1] = {
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[NFCTH_TUPLE_L3PROTONUM] = { .type = NLA_U16, },
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[NFCTH_TUPLE_L4PROTONUM] = { .type = NLA_U8, },
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};
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static int
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nfnl_cthelper_parse_tuple(struct nf_conntrack_tuple *tuple,
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const struct nlattr *attr)
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{
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struct nlattr *tb[NFCTH_TUPLE_MAX+1];
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nla_parse_nested(tb, NFCTH_TUPLE_MAX, attr, nfnl_cthelper_tuple_pol);
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if (!tb[NFCTH_TUPLE_L3PROTONUM] || !tb[NFCTH_TUPLE_L4PROTONUM])
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return -EINVAL;
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tuple->src.l3num = ntohs(nla_get_be16(tb[NFCTH_TUPLE_L3PROTONUM]));
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tuple->dst.protonum = nla_get_u8(tb[NFCTH_TUPLE_L4PROTONUM]);
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return 0;
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}
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static int
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nfnl_cthelper_from_nlattr(struct nlattr *attr, struct nf_conn *ct)
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{
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const struct nf_conn_help *help = nfct_help(ct);
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if (attr == NULL)
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return -EINVAL;
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if (help->helper->data_len == 0)
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return -EINVAL;
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memcpy(&help->data, nla_data(attr), help->helper->data_len);
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return 0;
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}
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static int
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nfnl_cthelper_to_nlattr(struct sk_buff *skb, const struct nf_conn *ct)
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{
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const struct nf_conn_help *help = nfct_help(ct);
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if (help->helper->data_len &&
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nla_put(skb, CTA_HELP_INFO, help->helper->data_len, &help->data))
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goto nla_put_failure;
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return 0;
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nla_put_failure:
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return -ENOSPC;
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}
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static const struct nla_policy nfnl_cthelper_expect_pol[NFCTH_POLICY_MAX+1] = {
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[NFCTH_POLICY_NAME] = { .type = NLA_NUL_STRING,
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.len = NF_CT_HELPER_NAME_LEN-1 },
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[NFCTH_POLICY_EXPECT_MAX] = { .type = NLA_U32, },
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[NFCTH_POLICY_EXPECT_TIMEOUT] = { .type = NLA_U32, },
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};
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static int
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nfnl_cthelper_expect_policy(struct nf_conntrack_expect_policy *expect_policy,
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const struct nlattr *attr)
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{
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struct nlattr *tb[NFCTH_POLICY_MAX+1];
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nla_parse_nested(tb, NFCTH_POLICY_MAX, attr, nfnl_cthelper_expect_pol);
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if (!tb[NFCTH_POLICY_NAME] ||
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!tb[NFCTH_POLICY_EXPECT_MAX] ||
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!tb[NFCTH_POLICY_EXPECT_TIMEOUT])
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return -EINVAL;
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strncpy(expect_policy->name,
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nla_data(tb[NFCTH_POLICY_NAME]), NF_CT_HELPER_NAME_LEN);
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expect_policy->max_expected =
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ntohl(nla_get_be32(tb[NFCTH_POLICY_EXPECT_MAX]));
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expect_policy->timeout =
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ntohl(nla_get_be32(tb[NFCTH_POLICY_EXPECT_TIMEOUT]));
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return 0;
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}
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static const struct nla_policy
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nfnl_cthelper_expect_policy_set[NFCTH_POLICY_SET_MAX+1] = {
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[NFCTH_POLICY_SET_NUM] = { .type = NLA_U32, },
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};
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static int
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nfnl_cthelper_parse_expect_policy(struct nf_conntrack_helper *helper,
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const struct nlattr *attr)
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{
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int i, ret;
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struct nf_conntrack_expect_policy *expect_policy;
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struct nlattr *tb[NFCTH_POLICY_SET_MAX+1];
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nla_parse_nested(tb, NFCTH_POLICY_SET_MAX, attr,
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nfnl_cthelper_expect_policy_set);
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if (!tb[NFCTH_POLICY_SET_NUM])
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return -EINVAL;
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helper->expect_class_max =
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ntohl(nla_get_be32(tb[NFCTH_POLICY_SET_NUM]));
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if (helper->expect_class_max != 0 &&
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helper->expect_class_max > NF_CT_MAX_EXPECT_CLASSES)
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return -EOVERFLOW;
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expect_policy = kzalloc(sizeof(struct nf_conntrack_expect_policy) *
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helper->expect_class_max, GFP_KERNEL);
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if (expect_policy == NULL)
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return -ENOMEM;
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for (i=0; i<helper->expect_class_max; i++) {
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if (!tb[NFCTH_POLICY_SET+i])
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goto err;
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ret = nfnl_cthelper_expect_policy(&expect_policy[i],
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tb[NFCTH_POLICY_SET+i]);
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if (ret < 0)
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goto err;
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}
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helper->expect_policy = expect_policy;
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return 0;
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err:
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kfree(expect_policy);
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return -EINVAL;
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}
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static int
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nfnl_cthelper_create(const struct nlattr * const tb[],
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struct nf_conntrack_tuple *tuple)
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{
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struct nf_conntrack_helper *helper;
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int ret;
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if (!tb[NFCTH_TUPLE] || !tb[NFCTH_POLICY] || !tb[NFCTH_PRIV_DATA_LEN])
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return -EINVAL;
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helper = kzalloc(sizeof(struct nf_conntrack_helper), GFP_KERNEL);
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if (helper == NULL)
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return -ENOMEM;
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ret = nfnl_cthelper_parse_expect_policy(helper, tb[NFCTH_POLICY]);
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if (ret < 0)
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goto err;
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strncpy(helper->name, nla_data(tb[NFCTH_NAME]), NF_CT_HELPER_NAME_LEN);
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helper->data_len = ntohl(nla_get_be32(tb[NFCTH_PRIV_DATA_LEN]));
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helper->flags |= NF_CT_HELPER_F_USERSPACE;
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memcpy(&helper->tuple, tuple, sizeof(struct nf_conntrack_tuple));
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helper->me = THIS_MODULE;
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helper->help = nfnl_userspace_cthelper;
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helper->from_nlattr = nfnl_cthelper_from_nlattr;
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helper->to_nlattr = nfnl_cthelper_to_nlattr;
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/* Default to queue number zero, this can be updated at any time. */
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if (tb[NFCTH_QUEUE_NUM])
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helper->queue_num = ntohl(nla_get_be32(tb[NFCTH_QUEUE_NUM]));
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if (tb[NFCTH_STATUS]) {
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int status = ntohl(nla_get_be32(tb[NFCTH_STATUS]));
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switch(status) {
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case NFCT_HELPER_STATUS_ENABLED:
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helper->flags |= NF_CT_HELPER_F_CONFIGURED;
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break;
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case NFCT_HELPER_STATUS_DISABLED:
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helper->flags &= ~NF_CT_HELPER_F_CONFIGURED;
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break;
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}
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}
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ret = nf_conntrack_helper_register(helper);
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if (ret < 0)
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goto err;
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return 0;
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err:
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kfree(helper);
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return ret;
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}
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static int
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nfnl_cthelper_update(const struct nlattr * const tb[],
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struct nf_conntrack_helper *helper)
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{
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int ret;
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if (tb[NFCTH_PRIV_DATA_LEN])
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return -EBUSY;
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if (tb[NFCTH_POLICY]) {
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ret = nfnl_cthelper_parse_expect_policy(helper,
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tb[NFCTH_POLICY]);
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if (ret < 0)
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return ret;
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}
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if (tb[NFCTH_QUEUE_NUM])
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helper->queue_num = ntohl(nla_get_be32(tb[NFCTH_QUEUE_NUM]));
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if (tb[NFCTH_STATUS]) {
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int status = ntohl(nla_get_be32(tb[NFCTH_STATUS]));
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switch(status) {
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case NFCT_HELPER_STATUS_ENABLED:
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helper->flags |= NF_CT_HELPER_F_CONFIGURED;
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break;
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case NFCT_HELPER_STATUS_DISABLED:
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helper->flags &= ~NF_CT_HELPER_F_CONFIGURED;
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break;
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}
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}
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return 0;
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}
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static int
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nfnl_cthelper_new(struct sock *nfnl, struct sk_buff *skb,
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const struct nlmsghdr *nlh, const struct nlattr * const tb[])
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{
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const char *helper_name;
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struct nf_conntrack_helper *cur, *helper = NULL;
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struct nf_conntrack_tuple tuple;
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int ret = 0, i;
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if (!tb[NFCTH_NAME] || !tb[NFCTH_TUPLE])
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return -EINVAL;
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helper_name = nla_data(tb[NFCTH_NAME]);
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ret = nfnl_cthelper_parse_tuple(&tuple, tb[NFCTH_TUPLE]);
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if (ret < 0)
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return ret;
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rcu_read_lock();
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for (i = 0; i < nf_ct_helper_hsize && !helper; i++) {
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hlist_for_each_entry_rcu(cur, &nf_ct_helper_hash[i], hnode) {
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/* skip non-userspace conntrack helpers. */
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if (!(cur->flags & NF_CT_HELPER_F_USERSPACE))
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continue;
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if (strncmp(cur->name, helper_name,
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NF_CT_HELPER_NAME_LEN) != 0)
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continue;
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if ((tuple.src.l3num != cur->tuple.src.l3num ||
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tuple.dst.protonum != cur->tuple.dst.protonum))
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continue;
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if (nlh->nlmsg_flags & NLM_F_EXCL) {
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ret = -EEXIST;
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goto err;
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}
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helper = cur;
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break;
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}
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}
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rcu_read_unlock();
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if (helper == NULL)
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ret = nfnl_cthelper_create(tb, &tuple);
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else
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ret = nfnl_cthelper_update(tb, helper);
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return ret;
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err:
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rcu_read_unlock();
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return ret;
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}
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static int
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nfnl_cthelper_dump_tuple(struct sk_buff *skb,
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struct nf_conntrack_helper *helper)
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{
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struct nlattr *nest_parms;
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nest_parms = nla_nest_start(skb, NFCTH_TUPLE | NLA_F_NESTED);
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if (nest_parms == NULL)
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goto nla_put_failure;
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if (nla_put_be16(skb, NFCTH_TUPLE_L3PROTONUM,
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htons(helper->tuple.src.l3num)))
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goto nla_put_failure;
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if (nla_put_u8(skb, NFCTH_TUPLE_L4PROTONUM, helper->tuple.dst.protonum))
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goto nla_put_failure;
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nla_nest_end(skb, nest_parms);
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return 0;
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nla_put_failure:
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return -1;
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}
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static int
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nfnl_cthelper_dump_policy(struct sk_buff *skb,
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struct nf_conntrack_helper *helper)
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{
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int i;
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struct nlattr *nest_parms1, *nest_parms2;
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nest_parms1 = nla_nest_start(skb, NFCTH_POLICY | NLA_F_NESTED);
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if (nest_parms1 == NULL)
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goto nla_put_failure;
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if (nla_put_be32(skb, NFCTH_POLICY_SET_NUM,
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htonl(helper->expect_class_max)))
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goto nla_put_failure;
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for (i=0; i<helper->expect_class_max; i++) {
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nest_parms2 = nla_nest_start(skb,
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(NFCTH_POLICY_SET+i) | NLA_F_NESTED);
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if (nest_parms2 == NULL)
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goto nla_put_failure;
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if (nla_put_string(skb, NFCTH_POLICY_NAME,
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helper->expect_policy[i].name))
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goto nla_put_failure;
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if (nla_put_be32(skb, NFCTH_POLICY_EXPECT_MAX,
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htonl(helper->expect_policy[i].max_expected)))
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goto nla_put_failure;
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if (nla_put_be32(skb, NFCTH_POLICY_EXPECT_TIMEOUT,
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htonl(helper->expect_policy[i].timeout)))
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goto nla_put_failure;
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nla_nest_end(skb, nest_parms2);
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}
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nla_nest_end(skb, nest_parms1);
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return 0;
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nla_put_failure:
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return -1;
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}
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static int
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nfnl_cthelper_fill_info(struct sk_buff *skb, u32 portid, u32 seq, u32 type,
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int event, struct nf_conntrack_helper *helper)
|
|
{
|
|
struct nlmsghdr *nlh;
|
|
struct nfgenmsg *nfmsg;
|
|
unsigned int flags = portid ? NLM_F_MULTI : 0;
|
|
int status;
|
|
|
|
event |= NFNL_SUBSYS_CTHELPER << 8;
|
|
nlh = nlmsg_put(skb, portid, seq, event, sizeof(*nfmsg), flags);
|
|
if (nlh == NULL)
|
|
goto nlmsg_failure;
|
|
|
|
nfmsg = nlmsg_data(nlh);
|
|
nfmsg->nfgen_family = AF_UNSPEC;
|
|
nfmsg->version = NFNETLINK_V0;
|
|
nfmsg->res_id = 0;
|
|
|
|
if (nla_put_string(skb, NFCTH_NAME, helper->name))
|
|
goto nla_put_failure;
|
|
|
|
if (nla_put_be32(skb, NFCTH_QUEUE_NUM, htonl(helper->queue_num)))
|
|
goto nla_put_failure;
|
|
|
|
if (nfnl_cthelper_dump_tuple(skb, helper) < 0)
|
|
goto nla_put_failure;
|
|
|
|
if (nfnl_cthelper_dump_policy(skb, helper) < 0)
|
|
goto nla_put_failure;
|
|
|
|
if (nla_put_be32(skb, NFCTH_PRIV_DATA_LEN, htonl(helper->data_len)))
|
|
goto nla_put_failure;
|
|
|
|
if (helper->flags & NF_CT_HELPER_F_CONFIGURED)
|
|
status = NFCT_HELPER_STATUS_ENABLED;
|
|
else
|
|
status = NFCT_HELPER_STATUS_DISABLED;
|
|
|
|
if (nla_put_be32(skb, NFCTH_STATUS, htonl(status)))
|
|
goto nla_put_failure;
|
|
|
|
nlmsg_end(skb, nlh);
|
|
return skb->len;
|
|
|
|
nlmsg_failure:
|
|
nla_put_failure:
|
|
nlmsg_cancel(skb, nlh);
|
|
return -1;
|
|
}
|
|
|
|
static int
|
|
nfnl_cthelper_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
|
|
{
|
|
struct nf_conntrack_helper *cur, *last;
|
|
|
|
rcu_read_lock();
|
|
last = (struct nf_conntrack_helper *)cb->args[1];
|
|
for (; cb->args[0] < nf_ct_helper_hsize; cb->args[0]++) {
|
|
restart:
|
|
hlist_for_each_entry_rcu(cur,
|
|
&nf_ct_helper_hash[cb->args[0]], hnode) {
|
|
|
|
/* skip non-userspace conntrack helpers. */
|
|
if (!(cur->flags & NF_CT_HELPER_F_USERSPACE))
|
|
continue;
|
|
|
|
if (cb->args[1]) {
|
|
if (cur != last)
|
|
continue;
|
|
cb->args[1] = 0;
|
|
}
|
|
if (nfnl_cthelper_fill_info(skb,
|
|
NETLINK_CB(cb->skb).portid,
|
|
cb->nlh->nlmsg_seq,
|
|
NFNL_MSG_TYPE(cb->nlh->nlmsg_type),
|
|
NFNL_MSG_CTHELPER_NEW, cur) < 0) {
|
|
cb->args[1] = (unsigned long)cur;
|
|
goto out;
|
|
}
|
|
}
|
|
}
|
|
if (cb->args[1]) {
|
|
cb->args[1] = 0;
|
|
goto restart;
|
|
}
|
|
out:
|
|
rcu_read_unlock();
|
|
return skb->len;
|
|
}
|
|
|
|
static int
|
|
nfnl_cthelper_get(struct sock *nfnl, struct sk_buff *skb,
|
|
const struct nlmsghdr *nlh, const struct nlattr * const tb[])
|
|
{
|
|
int ret = -ENOENT, i;
|
|
struct nf_conntrack_helper *cur;
|
|
struct sk_buff *skb2;
|
|
char *helper_name = NULL;
|
|
struct nf_conntrack_tuple tuple;
|
|
bool tuple_set = false;
|
|
|
|
if (nlh->nlmsg_flags & NLM_F_DUMP) {
|
|
struct netlink_dump_control c = {
|
|
.dump = nfnl_cthelper_dump_table,
|
|
};
|
|
return netlink_dump_start(nfnl, skb, nlh, &c);
|
|
}
|
|
|
|
if (tb[NFCTH_NAME])
|
|
helper_name = nla_data(tb[NFCTH_NAME]);
|
|
|
|
if (tb[NFCTH_TUPLE]) {
|
|
ret = nfnl_cthelper_parse_tuple(&tuple, tb[NFCTH_TUPLE]);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
tuple_set = true;
|
|
}
|
|
|
|
for (i = 0; i < nf_ct_helper_hsize; i++) {
|
|
hlist_for_each_entry_rcu(cur, &nf_ct_helper_hash[i], hnode) {
|
|
|
|
/* skip non-userspace conntrack helpers. */
|
|
if (!(cur->flags & NF_CT_HELPER_F_USERSPACE))
|
|
continue;
|
|
|
|
if (helper_name && strncmp(cur->name, helper_name,
|
|
NF_CT_HELPER_NAME_LEN) != 0) {
|
|
continue;
|
|
}
|
|
if (tuple_set &&
|
|
(tuple.src.l3num != cur->tuple.src.l3num ||
|
|
tuple.dst.protonum != cur->tuple.dst.protonum))
|
|
continue;
|
|
|
|
skb2 = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
|
|
if (skb2 == NULL) {
|
|
ret = -ENOMEM;
|
|
break;
|
|
}
|
|
|
|
ret = nfnl_cthelper_fill_info(skb2, NETLINK_CB(skb).portid,
|
|
nlh->nlmsg_seq,
|
|
NFNL_MSG_TYPE(nlh->nlmsg_type),
|
|
NFNL_MSG_CTHELPER_NEW, cur);
|
|
if (ret <= 0) {
|
|
kfree_skb(skb2);
|
|
break;
|
|
}
|
|
|
|
ret = netlink_unicast(nfnl, skb2, NETLINK_CB(skb).portid,
|
|
MSG_DONTWAIT);
|
|
if (ret > 0)
|
|
ret = 0;
|
|
|
|
/* this avoids a loop in nfnetlink. */
|
|
return ret == -EAGAIN ? -ENOBUFS : ret;
|
|
}
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
static int
|
|
nfnl_cthelper_del(struct sock *nfnl, struct sk_buff *skb,
|
|
const struct nlmsghdr *nlh, const struct nlattr * const tb[])
|
|
{
|
|
char *helper_name = NULL;
|
|
struct nf_conntrack_helper *cur;
|
|
struct hlist_node *tmp;
|
|
struct nf_conntrack_tuple tuple;
|
|
bool tuple_set = false, found = false;
|
|
int i, j = 0, ret;
|
|
|
|
if (tb[NFCTH_NAME])
|
|
helper_name = nla_data(tb[NFCTH_NAME]);
|
|
|
|
if (tb[NFCTH_TUPLE]) {
|
|
ret = nfnl_cthelper_parse_tuple(&tuple, tb[NFCTH_TUPLE]);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
tuple_set = true;
|
|
}
|
|
|
|
for (i = 0; i < nf_ct_helper_hsize; i++) {
|
|
hlist_for_each_entry_safe(cur, tmp, &nf_ct_helper_hash[i],
|
|
hnode) {
|
|
/* skip non-userspace conntrack helpers. */
|
|
if (!(cur->flags & NF_CT_HELPER_F_USERSPACE))
|
|
continue;
|
|
|
|
j++;
|
|
|
|
if (helper_name && strncmp(cur->name, helper_name,
|
|
NF_CT_HELPER_NAME_LEN) != 0) {
|
|
continue;
|
|
}
|
|
if (tuple_set &&
|
|
(tuple.src.l3num != cur->tuple.src.l3num ||
|
|
tuple.dst.protonum != cur->tuple.dst.protonum))
|
|
continue;
|
|
|
|
found = true;
|
|
nf_conntrack_helper_unregister(cur);
|
|
}
|
|
}
|
|
/* Make sure we return success if we flush and there is no helpers */
|
|
return (found || j == 0) ? 0 : -ENOENT;
|
|
}
|
|
|
|
static const struct nla_policy nfnl_cthelper_policy[NFCTH_MAX+1] = {
|
|
[NFCTH_NAME] = { .type = NLA_NUL_STRING,
|
|
.len = NF_CT_HELPER_NAME_LEN-1 },
|
|
[NFCTH_QUEUE_NUM] = { .type = NLA_U32, },
|
|
};
|
|
|
|
static const struct nfnl_callback nfnl_cthelper_cb[NFNL_MSG_CTHELPER_MAX] = {
|
|
[NFNL_MSG_CTHELPER_NEW] = { .call = nfnl_cthelper_new,
|
|
.attr_count = NFCTH_MAX,
|
|
.policy = nfnl_cthelper_policy },
|
|
[NFNL_MSG_CTHELPER_GET] = { .call = nfnl_cthelper_get,
|
|
.attr_count = NFCTH_MAX,
|
|
.policy = nfnl_cthelper_policy },
|
|
[NFNL_MSG_CTHELPER_DEL] = { .call = nfnl_cthelper_del,
|
|
.attr_count = NFCTH_MAX,
|
|
.policy = nfnl_cthelper_policy },
|
|
};
|
|
|
|
static const struct nfnetlink_subsystem nfnl_cthelper_subsys = {
|
|
.name = "cthelper",
|
|
.subsys_id = NFNL_SUBSYS_CTHELPER,
|
|
.cb_count = NFNL_MSG_CTHELPER_MAX,
|
|
.cb = nfnl_cthelper_cb,
|
|
};
|
|
|
|
MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTHELPER);
|
|
|
|
static int __init nfnl_cthelper_init(void)
|
|
{
|
|
int ret;
|
|
|
|
ret = nfnetlink_subsys_register(&nfnl_cthelper_subsys);
|
|
if (ret < 0) {
|
|
pr_err("nfnl_cthelper: cannot register with nfnetlink.\n");
|
|
goto err_out;
|
|
}
|
|
return 0;
|
|
err_out:
|
|
return ret;
|
|
}
|
|
|
|
static void __exit nfnl_cthelper_exit(void)
|
|
{
|
|
struct nf_conntrack_helper *cur;
|
|
struct hlist_node *tmp;
|
|
int i;
|
|
|
|
nfnetlink_subsys_unregister(&nfnl_cthelper_subsys);
|
|
|
|
for (i=0; i<nf_ct_helper_hsize; i++) {
|
|
hlist_for_each_entry_safe(cur, tmp, &nf_ct_helper_hash[i],
|
|
hnode) {
|
|
/* skip non-userspace conntrack helpers. */
|
|
if (!(cur->flags & NF_CT_HELPER_F_USERSPACE))
|
|
continue;
|
|
|
|
nf_conntrack_helper_unregister(cur);
|
|
}
|
|
}
|
|
}
|
|
|
|
module_init(nfnl_cthelper_init);
|
|
module_exit(nfnl_cthelper_exit);
|